With arrival of an intelligent era and an Internet of things era, a data bandwidth is greatly increased. A future radio access network needs to meet a requirement for a rapid bandwidth increase, and further needs to provide cheap wireless broadband Internet access for a user. The future radio access network needs to meet the following conditions: (1) reducing energy consumption and reducing capital expenditure and operating expenditure; (2) improving frequency spectrum efficiency and increasing a user bandwidth; (3) opening a platform and supporting multiple standards and smooth upgrade; and (4) providing a better Internet service for an end user.
Based on a centralized baseband processing pool, a cooperative wireless network that includes a remote radio frequency unit and an antenna, and a (Centralized/Cooperative/Cloud Radio Access Network (C-RAN) of a real-time cloud-type infrastructure of an open platform, a requirement for synchronous development between operator revenues and a future mobile Internet service can be met.
A fiber direct connection manner is used in a conventional communication method. However, because of a growing number of deployed Remote Radio Units (RRU), costs of this manner increase rapidly. Therefore, a solution is currently used. In this solution, an Optical Transport Network (OTN) device is disposed between an RRU and a Baseband Unit (BBU) to reduce deployment costs.
However, because 8B/10B (or 64B/66B) encoding is used in the existing solution, redundant overheads are caused after a Common Public Radio interface (CPRI) service is encoded. In the existing solution, the CPRI service is directly and transparently mapped into an Optical Transport Unit (OTU) frame for transmission. Therefore, the redundant overheads are mapped for transmission in this solution, thereby wasting transmission bandwidth resources, and resulting in low data transmission efficiency.